'\"
'\" Copyright (c) 2007 Donal K. Fellows
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
.TH my n 0.1 TclOO "TclOO Commands"
.so man.macros
.BS
'\" Note:  do not modify the .SH NAME line immediately below!
.SH NAME
my, myclass \- invoke any method of current object or its class
.SH SYNOPSIS
.nf
package require TclOO

\fBmy\fI methodName\fR ?\fIarg ...\fR?
\fBmyclass\fI methodName\fR ?\fIarg ...\fR?
.fi
.BE
.SH DESCRIPTION
.PP
The \fBmy\fR command is used to allow methods of objects to invoke methods
of the object (or its class),
.VS TIP478
and the \fBmyclass\fR command is used to allow methods of objects to invoke
methods of the current class of the object \fIas an object\fR.
.VE TIP478
In particular, the set of valid values for
\fImethodName\fR is the set of all methods supported by an object and its
superclasses, including those that are not exported
.VS TIP500
and private methods of the object or class when used within another method
defined by that object or class.
.VE TIP500
.PP
The object upon which the method is invoked via \fBmy\fR is the one that owns
the namespace that the \fBmy\fR command is contained in initially (\fBNB:\fR the link
remains if the command is renamed), which is the currently invoked object by
default.
.VS TIP478
Similarly, the object on which the method is invoked via \fBmyclass\fR is the
object that is the current class of the object that owns the namespace that
the \fBmyclass\fR command is contained in initially. As with \fBmy\fR, the
link remains even if the command is renamed into another namespace, and
defaults to being the manufacturing class of the current object.
.VE TIP478
.PP
Each object has its own \fBmy\fR and \fBmyclass\fR commands, contained in its
instance namespace.
.SH EXAMPLES
.PP
This example shows basic use of \fBmy\fR to use the \fBvariables\fR method of
the \fBoo::object\fR class, which is not publicly visible by default:
.PP
.CS
oo::class create c {
    method count {} {
        \fBmy\fR variable counter
        puts [incr counter]
    }
}

c create o
o count              \fI\(-> prints "1"\fR
o count              \fI\(-> prints "2"\fR
o count              \fI\(-> prints "3"\fR
.CE
.PP
This example shows how you can use \fBmy\fR to make callbacks to private
methods from outside the object (from a \fBtrace\fR), using
\fBnamespace code\fR to enter the correct context. (See the \fBcallback\fR
command for the recommended way of doing this.)
.PP
.CS
oo::class create HasCallback {
    method makeCallback {} {
        return [namespace code {
            \fBmy\fR Callback
        }]
    }

    method Callback {args} {
        puts "callback: $args"
    }
}

set o [HasCallback new]
trace add variable xyz write [$o makeCallback]
set xyz "called"     \fI\(-> prints "callback: xyz {} write"\fR
.CE
.PP
.VS TIP478
This example shows how to access a private method of a class from an instance
of that class. (See the \fBclassmethod\fR declaration in \fBoo::define\fR for
a higher level interface for doing this.)
.PP
.CS
oo::class create CountedSteps {
    self {
        variable count
        method Count {} {
            return [incr count]
        }
    }
    method advanceTwice {} {
        puts "in [self] step A: [\fBmyclass\fR Count]"
        puts "in [self] step B: [\fBmyclass\fR Count]"
    }
}

CountedSteps create x
CountedSteps create y
x advanceTwice       \fI\(-> prints "in ::x step A: 1"\fR
                     \fI\(-> prints "in ::x step B: 2"\fR
y advanceTwice       \fI\(-> prints "in ::y step A: 3"\fR
                     \fI\(-> prints "in ::y step B: 4"\fR
x advanceTwice       \fI\(-> prints "in ::x step A: 5"\fR
                     \fI\(-> prints "in ::x step B: 6"\fR
y advanceTwice       \fI\(-> prints "in ::y step A: 7"\fR
                     \fI\(-> prints "in ::y step B: 8"\fR
.CE
.VE TIP478
.SH "SEE ALSO"
next(n), oo::object(n), self(n)
.SH KEYWORDS
method, method visibility, object, private method, public method
.\" Local variables:
.\" mode: nroff
.\" fill-column: 78
.\" End:
